Conventionally, when an infusion is performed on a patient, a plurality of tubes are connected to form an infusion line extending from an infusion bag to the patient, and the plurality of tubes are connected through a connector. Additionally, during infusion, a second infusion solution may be supplied from another (second) line to a main line which supplies a main infusion solution to the patient. The second infusion solution is mixed with the main infusion solution at the connector and then conducted to the patient. In this case, a connector including a three-way port configured to mix a plurality of infusion solutions is employed (see JP 2010-505551 W).
The connector disclosed in JP 2010-505551 W includes first and second ports configured to constitute a flow channel of a main line, and a third port configured to constitute a flow channel of another (second) line, in a main body. In the third port, a space portion connected to an internal flow channel is provided at a position branched from the internal flow channel (flow channel of the main line) and configured to communicate between the flow channels of the first and second ports. The space portion is provided for insertion and connection of a male connector of the another (second) line.
In the space portion of the third port, a fluid infusion solution (or air or the like) may become entrapped while the male connector of the another line is not connected thereto (closed state of the third port). Fluid (hereinafter also referred to as trapped fluid) trapped in such a space portion may bring about various disadvantages, particularly, in a medical device.
For example, before the infusion solution is supplied to the patient, the infusion line is filled with the infusion solution to remove air, but an air bubble (air) may be trapped in the space portion, and when the infusion solution is then supplied to the patient, the remaining air bubble may be conducted to the patient with the infusion solution. In addition, when a high nutrient solution is supplied as the infusion solution, the nutrient solution trapped in the space portion may promote the growth of bacteria in the connector, and as a result, the bacteria may be conducted into the patient. Further, when a drug solution to be supplied to the patient is changed, a next drug solution is supplied while the previous drug solution remains in the space portion, so that the different drug solutions may be mixed and conducted to the patient.
In order to overcome the above-mentioned disadvantage, there is provided a connector provided with a wall portion (fluid flow director) on an internal flow channel, for conducting the infusion solution into a space portion, in order to promote draining of any trapped fluid.
However, the wall portion provided on the internal flow channel guides the infusion solution to the space portion, with a relatively small fluid force. Therefore, the infusion solution guided to the space portion only partially influences the trapped fluid filled in the space portion, and the trapped fluid is insufficiently drained from the space portion. As a result, the trapped fluid remains in the space portion, and the same above-mentioned disadvantage may occur.